Semiconductor device and wireless communication system using the same

ABSTRACT

Initialization of a semiconductor device can be efficiently performed, which transmits and receives data through wireless communication. The semiconductor device includes an antenna, a power source circuit, a circuit which uses a DC voltage generated by the power source circuit as a power source voltage, and a resistor. The antenna includes a pair of terminals and receives a wireless signal (a modulated carrier wave). The power source circuit includes a first terminal and a second terminal and generates a DC voltage between the first terminal and the second terminal by using a received wireless signal (the modulated carrier wave). The resistor is connected between the first terminal and the second terminal. In this manner, the semiconductor device and the wireless communication system can transmit and receive data accurately.

TECHNICAL FIELD

The present invention relates to a semiconductor device which cantransmit and receive data through wireless communication. Such asemiconductor device is called a wireless tag, an RF tag, an RFID tag,an IC tag, an ID tag, an electronic tag, a transponder, a wirelessmemory, an RFID chip, a wireless chip, an ID chip, a wireless IC card,an ID card, or the like. In particular, the invention relates to asemiconductor device which receives wireless signals generated from areader/writer through an antenna and generates a power source voltagerequired for operations.

BACKGROUND ART

As is called a ubiquitous information society, in recent years, anenvironment has been managed so that one can access the informationnetwork whenever and wherever he/she likes. In such an environment, anindividual authentication technique is attracting attentions, such thatan ID (identification number) is assigned to each object, thereby thehistory of the object is clarified and the manufacturing, management, orthe like is facilitated. In particular, a semiconductor device which cantransmit and receive data through wireless communication (hereinafteralso called a wireless tag) has started to be used.

FIG. 3A shows an example of a wireless communication system using awireless tag. The wireless communication system is formed of areader/writer 300, a control terminal 302, and a wireless tag 303. Thecontrol terminal 302 controls the reader/writer 300. Data is transmittedand received wirelessly between an antenna 301 connected to thereader/writer 300 and an antenna 304 in the wireless tag 303.

Wireless data transmission and reception are performed as follows. Theantenna 304 in the wireless tag 303 receives a wireless signal outputtedfrom the antenna 301 connected to the reader/writer 300. The wirelesssignal is an electromagnetic wave which is modulated in accordance withthe data to be transmitted. The electromagnetic wave for transmittingdata is called a carrier wave. A wireless signal is also called acarrier wave which is modulated in accordance with data. A wirelesssignal (a modulated carrier wave 330) is received by the antenna 304 andinputted to a signal processing circuit 305 in the wireless tag 303 tobe processed. In this manner, the wireless tag 303 obtains datacontained in the wireless signal (the modulated carrier wave 330).Subsequently, a signal containing response data is outputted from thesignal processing circuit 305. The antenna 304 in the wireless tag 303transmits a wireless signal (the modulated carrier wave 330)corresponding to the outputted signal to the antenna 301 connected tothe reader/writer 300. The wireless signal (the modulated carrier wave330) is received by the antenna 301 and the reader/writer 300 obtainsthe response data and accumulates the response data in the controlterminal 302.

The antenna 304 in the wireless tag 303 receiving a wireless signal (themodulated carrier wave 330) outputted from the antenna 301 connected tothe reader/writer 300, the wireless signal (the modulated carrier wave330) is inputted through a band-pass filter 306 to a power sourcecircuit 307 in the wireless tag 303. The power source circuit 307generates a power source voltage for driving an internal circuit(corresponding to the signal processing circuit 305 or the like) in thewireless tag 303 from the inputted wireless signal (the modulatedcarrier wave 330).

In specific, the power source circuit 307 includes a rectifying circuit308 which converts the inputted wireless signal (the modulated carrierwave 330) into a DC signal, and a holding capacitor 309 which smoothesthe DC signal. In this manner, the power source circuit 307 generates aDC voltage between a first terminal 310 and a second terminal 311. Thegenerated DC voltage is supplied as a power source voltage to aninternal circuit of the wireless tag 303.

A wireless tag which generates a power source voltage for driving aninternal circuit by using a wireless signal (the modulated carrier wave330) as described above is disclosed in, for example, Patent Document 1.

[Patent Document 1]

Japanese Patent Laid-open No. 2002-319007

DISCLOSURE OF INVENTION

In a wireless communication system using the wireless tag 303 as shownin FIG. 3A, the relation between the wireless signal (the modulatedcarrier wave 330) and the power source voltage generated by using thewireless signal (the modulated carrier wave 330) is schematically shownin FIG. 3B. The power source voltage is expressed by a change in apotential 331 of the second terminal 311 while fixing a potential 332 ofthe first terminal 310 constant. As shown in FIG. 3B, a period in whicha wireless signal (the modulated carrier wave 330) is outputted from theantenna 301 connected to the reader/writer 300 (referred to as a period1) and a period in which it is not outputted at all (referred to as aperiod 2) are alternately provided normally. In a period in which awireless signal (the modulated carrier wave 330) is not inputted, it isrequired that the power source voltage is decreased to zero or thepotential 331 of the second terminal 311 is decreased to be close to thepotential 332 of the first terminal 310.

The power source voltage is decreased to zero or the potential 331 ofthe second terminal 311 is decreased to be close to the potential 332 ofthe first terminal 310 in the period in which a wireless signal (themodulated carrier wave 330) is not inputted (the period 2) in order toinitialize the circuit in the wireless tag 303 by decreasing the powersource voltage of the wireless tag 303 to zero or a level close to zeroperiodically. In this manner, by initializing the circuit in thewireless tag 303 every time a new wireless signal (the modulated carrierwave 330) is received, the wireless tag 303 can receive a signaltransmitted from the reader/writer 300 accurately in accordance with thestandard, while the signal in accordance with the standard can beaccurately transmitted to the reader/writer 300.

However, in actuality, there is a problem that the power source voltagedoes not decrease to zero or the potential of the second terminal 311does not decrease to be close to the potential of the first terminal310. That is, there is a problem that a power source voltage of ΔV orhigher is always generated even in the period 2. In particular, theaforementioned problem is a big issue when the capacitance of theholding capacitor 309 of the power source circuit 307 is set as large asabout several hundreds pF in order to obtain a higher power sourcevoltage.

In the period 2, the wireless tag 303 cannot be initialized sufficientlyunless the power source voltage (voltage between the first terminal 310and the second terminal 311) becomes zero or the potential of the secondterminal 311 becomes close to the potential of the first terminal 310.Without being initialized, the wireless tag 303 cannot receive a signaltransmitted from the reader/writer 300 and transmit a signal in responseto the reader/writer 300. Further, in the case where the initializationis not performed, once the wireless tag 303 fails to receive a signal,all the following operations performed by the wireless tag 303 end inmalfunctions.

In view of the aforementioned, in the invention, initialization of asemiconductor device is efficiently performed, which transmits andreceives data through wireless communication.

In a semiconductor device of the invention which generates a powersource voltage from a carrier wave, a resistor is connected between apair of terminals (a first terminal and a second terminal) which applythe power source voltage to an internal circuit of the semiconductordevice.

That is, the semiconductor device of the invention includes an antenna,a power source circuit, a circuit which uses a DC voltage generated bythe power source circuit as a power source voltage, and a resistor. Theantenna includes a pair of terminals and receives a wireless signal (amodulated carrier wave). The power source circuit includes a firstterminal and a second terminal, and generates a DC voltage between thefirst terminal and the second terminal by using the received wirelesssignal (the modulated carrier wave). The resistor is connected betweenthe first terminal and the second terminal.

The semiconductor device of the invention can be efficientlyinitialized. Therefore, the semiconductor device of the invention cantransmit and receive data accurately. Moreover, the semiconductor deviceof the invention is initialized even when it fails to receive a signalonce, therefore, the following operations can be accurately performed.In this manner, a semiconductor device with high reliability and awireless communication system using the semiconductor device areprovided.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram showing a configuration of a semiconductor device ofthe invention.

FIG. 2 is a diagram showing a configuration of a semiconductor device ofthe invention.

FIG. 3A is a diagram showing a configuration of a conventionalsemiconductor device and FIG. 3B is a diagram showing characteristicsthereof.

FIG. 4A is a diagram showing characteristics of a semiconductor deviceof the invention and FIG. 4B is a diagram showing characteristics of aconventional semiconductor device.

FIG. 5 is a diagram showing a configuration of a reader/writer.

FIGS. 6A to 6D are views showing structures of antennas of asemiconductor device of the invention.

FIGS. 7A to 7C are views showing a manufacturing method of asemiconductor device of the invention and FIG. 7D is a view showing anapplication thereof.

FIGS. 8A to 8C are views showing a manufacturing method of asemiconductor device of the invention.

FIG. 9 is a diagram showing a configuration of a semiconductor device ofthe invention.

FIG. 10 is a view showing a configuration of a semiconductor device ofthe invention besides an antenna.

FIG. 11 is a view showing a configuration of a semiconductor device ofthe invention.

FIG. 12A is a diagram showing characteristics of a semiconductor deviceof the invention and FIG. 12B is a diagram showing characteristics of aconventional semiconductor device.

FIGS. 13A and 13B are views showing systems using a semiconductor deviceof the invention.

FIGS. 14A to 14E are views illustrating applications of a semiconductordevice of the invention.

FIGS. 15A and 15B are views showing a conventional method and a methodof the invention to lead wires of a semiconductor device respectively.

FIG. 16 is a diagram showing a configuration of a semiconductor deviceof the invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Although the invention will be fully described by way of embodimentmodes and embodiments with reference to the accompanying drawings, it isto be understood that various changes and modifications will be apparentto those skilled in the art. Therefore, unless such changes andmodifications depart from the scope of the invention, they should beconstrued as being included therein.

Embodiment Mode 1

A semiconductor device of the invention is described with reference toFIG. 1. It is to be noted that the same portions in FIG. 1 as those inFIGS. 3A and 3B are denoted by the same reference numerals. Thesemiconductor device 101 includes the antenna 304, the band-pass filter306, the power source circuit 307, a circuit which uses the DC voltagegenerated by the power source circuit 307 as a power source voltage (thesignal processing circuit 305 is shown as a representative), and aresistor 100. The antenna 304 includes a pair of terminals and receivesa wireless signal (a modulated carrier wave). The band-pass filter 306is connected between one of the pair of terminals of the antenna 304 andan input of the power source circuit 307. The power source circuit 307includes the first terminal 310 and the second terminal 311, andgenerates a DC voltage between the first terminal 310 and the secondterminal 311 by using the received wireless signal (the modulatedcarrier wave). The resistor 100 is connected between the first terminal310 and the second terminal 311.

The same potentials may be applied to the other of the pair of terminalsof the antenna 304 and the first terminal 310. The other of the pair ofterminals of the antenna 304 and the first terminal 310 may be grounded.

Further, the power source circuit 307 can be formed of the rectifyingcircuit 308 and the holding capacitor 309. The rectifying circuit 308rectifies a wireless signal (a modulated carrier wave) and converts itto a DC signal. The holding capacitor 309 smoothes the DC signaloutputted from the rectifying circuit 308. The signal smoothed by theholding capacitor 309 is outputted as a DC voltage between the firstterminal 310 and the second terminal 311. Either a circuit whichperforms full-wave rectification or a circuit which performs half-waverectification may be used as the rectifying circuit 308.

A resistor formed using a semiconductor layer can be used as theresistor 100. For example, the signal processing circuit 305 may beformed using a thin film transistor and the resistor 100 may be formedusing a semiconductor layer which is formed simultaneously with asemiconductor layer which functions as an active layer of the thin filmtransistor. In this case, impurity elements which impart conductivitymay be added to the semiconductor layer which forms the resistor 100. Ina resistor formed using a semiconductor layer to which impurity elementswhich impart conductivity are added, variations in resistance can beless than in a resistor formed using a semiconductor layer to whichimpurity elements which impart conductivity are not added. Inparticular, in the case of using a polycrystalline semiconductor film asa semiconductor layer which forms the resistor 100, variations inresistance caused by the variations in crystallinity of the film becomenotable. Therefore, it is effective to add impurity elements whichimpart conductivity to the semiconductor layer which forms the resistor100.

Impurity elements which impart conductivity may be added to thesemiconductor layer which forms the resistor 100 at approximately thesame concentration as those added to a channel forming region of thethin film transistor. In the case of using an amorphous semiconductorfilm formed by a CVD method or the like as a semiconductor layer, it isknown that the formed amorphous semiconductor film slightly has n-typeconductivity. By adding impurity elements which impart conductivity tothe amorphous semiconductor film, the conductivity of the semiconductorlayer can be nearly intrinsic and high resistance thereof can beobtained. As the resistor can be formed utilizing manufacturing steps ofa thin film transistor which forms the signal processing circuit 305,the manufacturing cost of a semiconductor device can be suppressed andthe yield thereof can be improved.

A diode or a thin film transistor may be used as the resistor 100. Forexample, a thin film transistor which is diode-connected (a gate and adrain thereof are electrically connected) may also be used.

The frequency of the carrier wave may be any one of 300 GHz to 3 THz asa submillimeter wave, 30 to 300 GHz as a millimeter wave, 3 to 30 GHz asa microwave, 300 MHz to 3 GHz as an ultra high wave, 30 to 300 MHz as avery high wave, 3 to 30 MHz as a short wave, 300 KHz to 3 MHz as amedium wave, 30 to 300 kHz as a long wave, and 3 to 30 kHz as a verylong wave.

The antenna 304 may be any one of a dipole antenna, a patch antenna, aloop antenna, and a Yagi antenna.

A wireless signal may be transmitted and received by the antenna 304 byany one of an electromagnetic coupling method, an electromagneticinduction method, and a radio wave method.

A wireless communication system of the invention can use a semiconductordevice 101, a reader/writer with a known structure, an antenna connectedto the reader/writer, and a control terminal for controlling thereader/writer. The semiconductor device 101 and the antenna connected tothe reader/writer communicate by one-way communication or two-waycommunication, employing any one of a Space Division Multiplex method, aPolarization Division Multiplex method, a Frequency Division Multiplexmethod, a Time Division Multiplex method, a Code Division Multiplexmethod, and an Orthogonal Frequency Division Multiplex method.

FIG. 4A shows a relation between a wireless signal (a modulated carrierwave) and a power source voltage (expressed by a change in the potential331 of the second terminal 311 while fixing the potential 332 of thefirst terminal 310 constant) generated by using the wireless signal (themodulated carrier wave) in a wireless communication system of theinvention using the semiconductor device 101. FIG. 4B shows a relationbetween a wireless signal (a modulated carrier wave) and a power sourcevoltage generated by using the wireless signal (the modulated carrierwave) in a wireless communication system using a conventionalsemiconductor device (the wireless tag 303).

In FIGS. 4A and 4B, a first signal 401 is a signal which corresponds tothe data transmitted from a reader/writer. A carrier wave which ismodulated in amplitude is used as the first signal 401 as an example. Itis to be noted that the carrier wave is modulated by analog modulationor digital modulation, for which any one of amplitude modulation, phasemodulation, frequency modulation, and spread spectrum may be employed.

A wireless communication system using a semiconductor device of theinvention can decrease a power source voltage to zero or decrease thepotential 331 of the second terminal 311 to be close to the potential332 of the first terminal 310 in a period (period 2) in which a wirelesssignal (the modulated carrier wave 330) is not inputted. Therefore, asemiconductor device which receives the first signal 401 transmittedfrom the reader/writer transmits a second signal 402 corresponding toresponse data. In this manner, the semiconductor device transmits andreceives data normally.

On the other hand, as shown in FIG. 4B, a wireless communication systemusing a conventional semiconductor device cannot decrease a power sourcevoltage to zero or decrease the potential 331 of the second terminal 311to be close to the potential 332 of the first terminal 310 in a period(period 2) in which a wireless signal (the modulated carrier wave 330)is not inputted. Therefore, a power source voltage of ΔV or higher isalways generated. As a result, a semiconductor device which receives thefirst signal 401 which is transmitted from a reader/writer cannotrespond (see waveforms 444 in FIG. 4B), which causes a malfunction indata transmission and reception.

As described above, the invention can provide a semiconductor devicewhich performs data transmission and reception normally and a wirelesscommunication system using the semiconductor device.

Embodiment Mode 2

In this embodiment mode, an example of the signal processing circuit 305in the semiconductor device 101 described in Embodiment Mode 1 isdescribed with reference to FIG. 2. It is to be noted that the sameportions in FIG. 2 as those in FIG. 1 are denoted by the same referencenumerals and detailed description thereof is omitted.

The signal processing circuit 305 includes a band-pass filter 200, ademodulation circuit 201, an analyzing circuit 202, and a memory 203. Awireless signal (a modulated carrier wave) received by the antenna 304is inputted to the demodulation circuit 201 through the band-pass filter200. The demodulation circuit 201 demodulates information from thewireless signal (the modulated carrier wave). The analyzing circuit 202analyzes the information demodulated by the demodulation circuit 201 andoutputs corresponding data. The memory 203 operates based on the dataanalyzed by the analyzing circuit 202. That is, the memory 203 storesthe data analyzed by the analyzing circuit 202. Alternatively, thememory 203 reads out the data stored in the memory 203. The data storedin the memory 203 may be data stored when the semiconductor device 101is manufactured, or data received by the semiconductor device 101through wireless communication and stored in the memory 203. It is to benoted that one or both of a rewritable memory and a non-rewritablememory can be used as the memory 203.

The memory 203 provided in the semiconductor device may be a DRAM(Dynamic Random Access Memory), an SRAM (Static Random Access Memory),an FeRAM (Ferroelectric Random Access Memory), a mask ROM (Read OnlyMemory), an EPROM (Electrically Programmable Read Only Memory), anEEPROM (Electrically Erasable and Programmable Read Only Memory), or aflash memory.

The signal processing circuit 305 can further include an encodingcircuit 204 and a modulation circuit 205. The encoding circuit 204encodes the data stored in the memory 203 in accordance with apredetermined standard and converts it to corresponding information. Themodulation circuit 205 outputs the modulated signal in accordance withthe information encoded by the encoding circuit 204.

The encoding circuit 204 has a circuit configuration capable of encodingbased on the standard, such as Manchester encoding, NRZ (Non ReturnZero) encoding, and Miller encoding.

FIG. 2 shows an example where the band-pass filter 200 is provided inaddition to the band-pass filter 306, however, the invention is notlimited to this. The band-pass filter 200 and the band-pass filter 306may be used in common.

This embodiment mode can be freely implemented in combination withEmbodiment Mode 1.

Embodiment Mode 3

In this embodiment mode, an example of a reader/writer of a wirelesscommunication system using the semiconductor device 101 described inEmbodiment Modes 1 and 2 is described with reference to FIG. 5.

A reader/writer 500 includes an oscillation circuit 501, an encodingcircuit 502, a modulation circuit 503, an amplifier circuit 504, aband-pass filter 506, an amplifier circuit 507, a demodulation circuit508, and an analyzing circuit 509. Moreover, an antenna 505 is connectedto the reader/writer 500.

First, description is made of the case where the reader/writer 500transmits a signal. The oscillation circuit 501 generates a signal of apredetermined frequency. The generated signal is inputted to themodulation circuit 503. The encoding circuit 502 encodes transmissiondata inputted from a control terminal 510 and converts it tocorresponding information. The modulation circuit 503 modulates thesignal in accordance with the encoded information. The modulated signalis inputted to the amplifier circuit 504 and amplified therein. Theamplified signal is transmitted as a wireless signal (a modulatedcarrier wave) from the antenna 505.

Next, description is made of the case where the reader/writer 500receives a signal. The wireless signal (the modulated carrier wave) isreceived by the antenna 505. The received wireless signal (the modulatedcarrier wave) is inputted to the band-pass filter 506 to remove noiseand the like therein. The signal which passed the band-pass filter 506is inputted to the amplifier circuit 507 and amplified therein. Theamplified signal is inputted to the demodulation circuit 508. Thedemodulation circuit 508 demodulates information from the inputtedsignal. The demodulated information is inputted to the analyzing circuit509. The analyzing circuit 509 analyzes the inputted information andobtains reception data. The obtained reception data is outputted to thecontrol terminal 510.

The encoding circuit 502 has a circuit configuration capable of encodingbased on the standard, such as Manchester encoding, NRZ (Non ReturnZero) encoding, and Miller encoding.

The antenna 505 may be any one of a dipole antenna, a patch antenna, aloop antenna, and a Yagi antenna.

A wireless signal (a modulated carrier wave) may be transmitted andreceived at the antenna 505 by any one of an electromagnetic couplingmethod, an electromagnetic induction method, and a radio wave method.

This embodiment mode can be freely implemented in combination withEmbodiment Modes 1 and 2.

Embodiment 1

In this embodiment, specific configurations of a semiconductor device ofthe invention are described with reference to FIGS. 6A to 7D.

FIGS. 6A to 6D show configuration examples of the antenna 304 in thesemiconductor device 101 shown in FIGS. 1 and 2. The antenna 304 can beprovided in two ways. FIGS. 6A and 6C show one way (hereinafter called afirst antenna configuration) while FIGS. 6B and 6D show the other way(hereinafter called a second antenna configuration). FIG. 6C is a crosssectional view along A-A′ in FIG. 6A and FIG. 6D is a cross sectionalview along B-B′ in FIG. 6B.

In the first antenna configuration, the antenna 304 is provided over asubstrate 600 provided with a plurality of elements (hereinafter calledan element group 601) (see FIGS. 6A and 6C). The element group 601 formscircuits other than the antenna of the semiconductor device of theinvention. The element group 601 includes a plurality of thin filmtransistors and the resistor 100. The resistor 100 is formed using asemiconductor layer 660 which is formed simultaneously with asemiconductor layer 662 which functions as an active layer of the thinfilm transistor. In the shown configuration, a conductive film whichfunctions as the antenna 304 is provided in the same layer as a wireconnected to a source or a drain of the thin film transistor in theelement group 601. However, the conductive film which functions as theantenna 304 may be provided in the same layer as a gate electrode 664 ofthe thin film transistor in the element group 601, or over an insulatingfilm which is provided so as to cover the element group 601.

In the second antenna configuration, a terminal portion 602 is providedover the substrate 600 provided with the element group 601. The antenna304 provided over a substrate 610 which is a different substrate fromthe substrate 600 is connected to the terminal portion 602 (see FIGS. 6Band 6D). In the shown configuration, a portion of a wire connected to asource or a drain of the thin film transistor in the element group 601is used as the terminal portion 602. The substrate 600 and the substrate610 provided with the antenna 304 are attached to each other so as to beconnected at the terminal portion 602. A conductive particle 603 and aresin 604 are provided between the substrate 600 and the substrate 610.The antenna 304 and the terminal portion 602 are electrically connectedby the conductive particle 603.

A configuration and a manufacturing method of the element group 601 aredescribed. Formed over a large substrate in a plural numbers and dividedlater to be completed by cutting the large substrate, the element groups601 can be inexpensively provided. As the substrate 600, for example, aglass substrate such as barium borosilicate glass and aluminoborosilicate glass, a quartz substrate, a ceramic substrate, or the likecan be used. Moreover, a semiconductor substrate over which aninsulating film is formed may be used as well. A substrate formed of asynthetic resin having flexibility such as plastic may also be used. Thesurface of the substrate may be planarized by polishing by a CMP methodor the like. Moreover, a substrate which is formed thin by polishing aglass substrate, a quartz substrate, or a semiconductor substrate may beused as well.

As a base film 661 provided over the substrate 600, an insulating filmsuch as silicon oxide, silicon nitride, or silicon nitride oxide can beused. The base film 661 can prevent an alkali metal such as Na or analkaline earth metal contained in the substrate 600 from dispersing intothe semiconductor layer 662 and adversely affecting the characteristicsof the thin film transistor. In FIGS. 6C and 6D, the base film 661 isformed of a single layer, however, it may be formed of two or morelayers. It is to be noted that the base film 661 is not always requiredto be provided when the dispersion of impurities is not a big problem,such as the case of using a quartz substrate.

It is to be noted that high density plasma may be directly applied tothe surface of the substrate 600. The high density plasma is, forexample, generated by using a high frequency of 2.45 GHz. It is to benoted that high density plasma with an electron density of 10¹¹ to 10¹³cm⁻³, an electron temperature of 2 eV or lower, and an ion energy of 5eV or lower is used. In this manner, high density plasma which featureslow electron temperature has low kinetic energy of active species,therefore, a film with less plasma damage and defects can be formed ascompared to conventional plasma treatment. Plasma can be generated byusing a plasma processing apparatus utilizing a radio frequencyexcitation, which employs a radial slot antenna. The antenna whichgenerates a radio frequency and the substrate 600 are placed at adistance of 20 to 80 mm (preferably 20 to 60 mm).

By performing the high density plasma treatment in an atmospherecontaining nitrogen (N) and rare gas (containing at least one of He, Ne,Ar, Kr, and Xe), an atmosphere containing nitrogen, hydrogen (H), andrare gas, or an atmosphere containing ammonium (NH₃) and rare gas, thesurface of the substrate 600 can be nitrided. In the case where thesubstrate 600 is formed of glass, quartz, a silicon wafer, or the like,a nitride layer formed over the surface of the substrate 600 containingsilicon nitride as a main component can be used as a blocking layeragainst impurities which are dispersed from the substrate 600 side. Asilicon oxide film or a silicon oxynitride film may be formed over thenitride layer by a plasma CVD method to be used as the base film 661.

By applying similar high density plasma treatment to the surface of thebase film 661 formed of silicon oxide or silicon oxynitride, the surfaceand a depth of 1 to 10 nm from the surface can be nitrided. Thisextremely thin silicon nitride layer is favorable since it functions asa blocking layer and has less stress on the semiconductor layer 662 andthe semiconductor layer 660 formed thereover.

A crystalline semiconductor film or an amorphous semiconductor filmprocessed into an arbitrary shape can be used as the semiconductor layer662 and the semiconductor layer 660. Moreover, an organic semiconductorfilm may also be used. A crystalline semiconductor film can be obtainedby crystallizing an amorphous semiconductor film. A lasercrystallization method, a thermal crystallization method using RTA or anannealing furnace, a thermal crystallization method using a metalelement which promotes crystallization, or the like can be used as thecrystallization method. The semiconductor layer 662 includes a channelforming region 662 a and a pair of impurity regions 662 b to whichimpurity elements which impart conductivity are added. Shown here is astructure where a low concentration impurity region 662 c to which theimpurity elements are added at a lower concentration than to theimpurity regions 662 b is provided between the channel forming region662 a and the pair of impurity regions 662 b, however, the invention isnot limited to this. The low concentration impurity region 662 c is notnecessarily provided. Impurity elements which impart conductivity may beadded to the entire surface of the semiconductor layer 660 or may not beadded thereto. In the case of adding impurity elements which impartconductivity, impurity elements which impart conductivity may be addedto the semiconductor layer 660 at approximately the same concentrationas the pair of impurity regions 662 b of the thin film transistor orimpurity elements which impart conductivity may be added thereto atapproximately the same concentration as the low concentration impurityregion 662 c.

It is to be noted that the semiconductor layer 662, the semiconductorlayer 660, and a wire which is formed simultaneously with these arepreferably lead so that corners are rounded when seen perpendicularly tothe top surface of the substrate 600. FIGS. 15A and 15B are schematicviews showing the method to lead the wires. In FIGS. 15A and 15B, adirection 351 is perpendicular to the top surface of the substrate 600.Wires 361 are formed simultaneously with the semiconductor layer. FIG.15A shows a conventional method to lead wires. FIG. 15B shows a methodof the invention to lead wires. Corner portions 1502 a of the wire 361of the invention are rounded as compared to corner portions 1501 a ofthe conventional wire 361. The rounded corner portions can prevent dustsor the like from remaining at the corner portions of the wire. In thismanner, defects of a semiconductor device caused by dusts can be reducedand the yield can be improved.

Impurity elements which impart conductivity may be added to the channelforming region 662 a of the thin film transistor. In this manner, athreshold voltage of the thin film transistor can be controlled. In thiscase, impurity elements which impart conductivity may be added to thesemiconductor layer 660 at approximately the same concentration as thechannel forming region 662 a of the thin film transistor.

A single layer or a stack of a plurality of layers formed of siliconoxide, silicon nitride, silicon nitride oxide or the like may be used asa first insulating film 663. In this case, high density plasma isapplied to the surface of the first insulating film 663 in an oxidizedatmosphere or a nitrided atmosphere, thereby the first insulating film663 may be oxidized or nitrided to be densified. The high density plasmais, for example, generated by using a high frequency of 2.45 GHz asdescribed above. It is to be noted that high density plasma with anelectron density of 10¹¹ to 10¹³/cm⁻³ or higher and an electrontemperature of 2 eV or lower, and an ion energy of 5 eV or lower isused. Plasma can be generated by using a plasma processing apparatusutilizing a radio frequency excitation, which employs a radial slotantenna. The antenna which generates a radio frequency and the substrate600 are placed at a distance of 20 to 80 mm (preferably 20 to 60 mm) inthe apparatus for generating high density plasma.

Before forming the first insulating film 663, the surface of thesemiconductor layer 662 may be oxidized or nitrided by applying the highdensity plasma treatment to the surfaces of the semiconductor layer 662and the semiconductor layer 660. At this time, by performing thetreatment in an oxidized atmosphere or a nitrided atmosphere with thesubstrate 600 at a temperature of 300 to 450° C., a favorable interfacecan be formed with the first insulating film 663 which is formedthereover.

As the nitrided atmosphere, an atmosphere containing nitrogen (N) andrare gas (containing at least one of He, Ne, Ar, Kr, and Xe), anatmosphere containing nitrogen, hydrogen (H), and rare gas, or anatmosphere containing ammonium (NH₃) and rare gas can be used. As theoxidized atmosphere, an atmosphere containing oxygen (O) and rare gas,an atmosphere containing oxygen and hydrogen (H), and rare gas or anatmosphere containing dinitrogen monoxide (N₂O) and rare gas can beused.

As the gate electrode 664, an element selected from Ta, W, Ti, Mo, Al,Cu, Cr, and Nd, an alloy or a compound containing a plurality of theaforementioned elements can be used. Alternatively, a single layerstructure or a stacked-layer structure formed of the aforementionedelement, an alloy or a compound thereof may also be employed. In thedrawings (FIGS. 6C, 6D), the gate electrode 664 has a two-layerstructure. It is to be noted that the gate electrode 664 and a wirewhich is formed simultaneously with the gate electrode 664 arepreferably led so that corner portions thereof are rounded when seenperpendicularly to the top surface of the substrate 600. The gateelectrode 664 and the wire can be led similarly to the method shown inFIG. 15B. The gate electrode 664 and the wire which is formedsimultaneously with the gate electrode 664 are shown as a wire 362 inthe drawings. By rounding corner portions 1502 b of the wire 362 of theinvention as compared to corner portions 1501 b of the conventional wire362, dusts or the like can be prevented from remaining at the cornerportions of the wire. In this manner, defects of a semiconductor devicecaused by dusts can be reduced and the yield can be improved.

A thin film transistor is formed of the semiconductor layer 662, thegate electrode 664, and a first insulating film 663 which functions as agate insulating film between the semiconductor layer 662 and the gateelectrode 664. In this embodiment, the thin film transistor has a topgate structure, however, it may be a bottom gate transistor having agate electrode under the semiconductor layer, or a dual gate transistorhaving gate electrodes over and under the semiconductor layer.

It is preferable that a second insulating film 667 is an insulating filmsuch as a silicon nitride film having a barrier property to block ionimpurities. The second insulating film 667 is formed of silicon nitrideor silicon oxynitride. The second insulating film 667 functions as aprotective film which prevents contamination of the semiconductor layer662 and the semiconductor layer 660. By introducing hydrogen gas andapplying the aforementioned high density plasma treatment afterdepositing the second insulating film 667, the second insulating film667 may be hydrogenated. Alternatively, the second insulating film 667may be nitrided and hydrogenated by introducing ammonium gas (NH₃).Otherwise, oxidization-nitridation treatment and hydrogenation treatmentmay be performed by introducing oxygen, dinitrogen monoxide (N₂O) gas,or the like together with hydrogen gas. By performing nitridationtreatment, oxidization treatment, or oxidization-nitridation treatmentby this method, the surface of the second insulating film 667 can bedensified. In this manner, a function of the second insulating film 667as a protective film can be enhanced. Hydrogen introduced in the secondinsulating film 667 is discharged when thermal treatment at 400 to 450°C. is applied, thereby the semiconductor layer 662 and the semiconductorlayer 660 can be hydrogenated. It is to be noted that the hydrogenationmay be performed in combination with hydrogenation using the firstinsulating film 663.

A third insulating film 665 can be formed of a single layer structure ora stacked-layer structure of an inorganic insulating film or an organicinsulating film. As an inorganic insulating film, a silicon oxide filmformed by a CVD method, a silicon oxide film formed by a SOG (Spin OnGlass) method, or the like can be used. As an organic insulating film, afilm formed of polyimide, polyamide, BCB (benzocyclobutene), acrylic, apositive photosensitive organic resin, a negative photosensitive organicresin, or the like can be used.

The third insulating film 665 may be formed of a material having askeleton structure formed of a bond of silicon (Si) and oxygen (O). Anorganic group containing at least hydrogen (such as an alkyl group oraromatic hydrocarbon) is used as a substituent of this material.Alternatively, a fluoro group may be used as the substituent. Furtheralternatively, a fluoro group and an organic group containing at leasthydrogen may be used as the substituent.

As a wire 666, one element selected from Al, Ni, W, Mo, Ti, Pt, Cu, Ta,Au, and Mn or an alloy containing a plurality of these elements can beused. Alternatively, a single layer structure or a stacked-layerstructure formed of the aforementioned element, an alloy or a compoundthereof can be used. In the drawing (FIGS. 6C, 6D), a single layerstructure is shown as an example. It is to be noted that the wire 666 ispreferably led so that corner portions thereof are rounded when seenperpendicularly to the top surface of the substrate 600. The wire can beled similarly to the method shown in FIG. 15B. The wire 666 is shown asa wire 363 in the drawings. By rounding corner portions 1502 c of thewire 363 of the invention as compared to corner portions 1501 c of theconventional wire 363, dusts or the like can be prevented from remainingat the corner portions of the wire. In this manner, defects of asemiconductor device caused by dusts can be reduced and the yield can beimproved. In the structures shown in FIGS. 6A and 6C, the wire 666functions as a wire connected to a source and a drain of a thin filmtransistor and also functions as the antenna 304. In the structuresshown in FIGS. 6B and 6D, the wire 666 functions as a wire connected toa source and a drain of the thin film transistor and also functions as aterminal portion 602. In FIGS. 15A and 15B, a contact hole 352 toconnect the wire 666 and the source and drain of the thin filmtransistor is provided.

It is to be noted that the antenna 304 can be formed by a dropletdischarge method using a conductive paste containing nano-particles suchas Au, Ag, and Cu. The droplet discharge method is a collective term fora method to form a pattern by discharging droplets, such as an ink jetmethod or a dispenser method, which has advantages in that utilizationefficiency of a material is improved, and the like.

In the structures shown in FIGS. 6A and 6C, a fourth insulating film 668is formed over the wire 666. As the fourth insulating film 668, a singlelayer structure or a stacked-layer structure of an inorganic insulatingfilm or an organic insulating film can be used. The fourth insulatingfilm 668 functions as a protective layer of the antenna 304.

The element group 601 formed over the substrate 600 (see FIG. 7A) may beused as it is, however, the element group 601 may be peeled off thesubstrate 600 (see FIG. 7B) and attached to a flexible substrate 701(see FIG. 7C). The flexible substrate 701 has flexibility, for which aplastic substrate, formed of polycarbonate, polyarylate, polyethersulfone, or the like, a ceramic substrate, or the like can be used.

The element group 601 may be peeled off the substrate 600 by (A)providing a peeling layer between the substrate 600 and the elementgroup 601 in advance and removing the peeling layer by using an etchant,(B) partially removing the peeling layer by using an etchant andphysically peeling the element group 601 from the substrate 600, or (C)mechanically removing the substrate 600 having high heat resistance overwhich the element group 601 is formed or removing it by etching withsolution or gas. It is to be noted that being physically peeled offcorresponds to being peeled off by external stress, for example, stressapplied by wind pressure blown from a nozzle, ultrasonic wave, and thelike.

The aforementioned methods (A) and (B) are specifically realized byproviding a metal oxide film between the substrate 600 having high heatresistance and the element group 601 and weakening the metal oxide filmby crystallization to peel off the element group 601, or by providing anamorphous silicon film containing hydrogen between the substrate 600having high heat resistance and the element group 601 and removing theamorphous silicon film by laser light irradiation or etching to peel offthe element group 601.

The element group 601 which has been peeled off may be attached to theflexible substrate 701 by using a commercialized adhesive, for example,an epoxy resin-based adhesive or a resin additive.

When the element group 601 is attached to the flexible substrate 701over which an antenna is formed so that the element group 601 and theantenna are electrically connected, a semiconductor device which isthin, lightweight, and can withstand shock when dropped is completed(see FIG. 7C). When the flexible substrate 701 is used, an inexpensivesemiconductor device can be provided. Moreover, as the flexiblesubstrate 701 has flexibility, it can be attached to a curved surface oran irregular surface, a variety of applications can be realized. Forexample, a wireless tag 720 as one mode of the semiconductor device ofthe invention can be tightly attached to, for example, a surface such asone of a medicine bottle (see FIG. 7D). Moreover, by reusing thesubstrate 600, a semiconductor device can be manufactured at low cost.

This embodiment can be freely implemented in combination with theaforementioned embodiment modes.

Embodiment 2

In this embodiment, a semiconductor device of the invention having aflexible structure is described with reference to FIGS. 8A to 8C. InFIG. 8A, a semiconductor device includes a flexible protective layer801, a flexible protective layer 803 including an antenna 802, and anelement group 804 formed by a peeling process and thinning of asubstrate. The element group 804 can have, for example, a similarstructure to that of the element group 601 described in Embodiment 1.The antenna 802 formed over the protective layer 803 is electricallyconnected to the element group 804. In FIG. 8A, the antenna 802 isformed only over the protective layer 803, however, the invention is notlimited to this structure and the antenna 802 may be formed over theprotective layer 801 as well. It is to be noted that a barrier filmformed of a silicon nitride film or the like may be formed between theelement group 804 and the protective layer 801, or between the elementgroup 804 and the protective layer 803. As a result, a semiconductordevice with improved reliability can be provided without contaminatingthe element group 804.

The antenna 802 can be formed of Ag, Cu, or a metal plated with Ag orCu. The element group 804 and the antenna 802 can be connected to eachother by using an anisotropic conductive film and applying ultraviolettreatment or ultrasonic wave treatment. It is to be noted that theelement group 804 and the antenna 802 may be attached to each other byusing a conductive paste.

By sandwiching the element group 804 by the protective layer 801 and theprotective layer 803, a semiconductor device is completed (see an arrowin FIG. 8A).

FIG. 8B shows a cross sectional structure of the semiconductor deviceformed in this manner. The element group 804 which is sandwiched has athickness 340 of 5 μm or thinner, or preferably 0.1 to 3 μm. Moreover,when the protective layer 801 and the protective layer 803 which areoverlapped have a thickness of d, each of the protective layer 801 andthe protective layer 803 preferably has a thickness of (d/2)±30 μm, andmore preferably (d/2)±10 μm. Further, it is preferable that each of theprotective layer 801 and the protective layer 803 have a thickness of 10to 200 μm. Furthermore, the element group 804 has an area of 10 mmsquare (100 mm²) or smaller and more preferably 0.3 to 4 mm square (0.09to 16 mm²).

The protective layer 801 and the protective layer 803 which are formedof an organic resin material have high resistance against bending. Theelement group 804 which is formed by a peeling process and thinning of asubstrate also has higher resistance against bending as compared to asingle crystal semiconductor. As the element group 804, the protectivelayer 801, and the protective layer 803 can be tightly attached to eachother without any space, a completed wireless tag has high resistanceagainst bending. The element group 804 surrounded by the protectivelayer 801 and the protective layer 803 may be provided over a surface ofor inside another object or embedded in paper.

Description is made with reference to FIG. 8C of the case of attaching asemiconductor device including the element group 804 to a substratehaving a curved surface. In FIG. 8C, one transistor 881 selected fromthe element group 804 is shown. In the transistor 881, a current flowsfrom one 805 of a source and a drain to the other 806 of the source andthe drain in accordance with a potential of a gate electrode 807. Thetransistor 881 is provided so that the direction of current flow in thetransistor 881 (carrier movement direction 341) and the direction of thearc of the substrate 880 cross at right angles. With such anarrangement, the transistor 881 is less affected by stress even when thesubstrate 880 is bent and draws an arc, and thus variations incharacteristics of the transistor 881 included in the element group 804can be suppressed.

This embodiment can be freely implemented in combination with theaforementioned embodiment modes and Embodiment 1.

Embodiment 3

In this embodiment, a more specific configuration of a semiconductordevice of the invention is described with reference to FIG. 9. It is tobe noted that the same portions in FIG. 9 to those in FIGS. 1 and 2 aredenoted by the same reference numerals and description thereof areomitted.

The semiconductor device 101 shown in FIG. 9 includes a resonantcapacitor 901 which is connected in parallel to the antenna 304. Withthe resonant capacitor 901, wireless signals at a predeterminedfrequency can be easily received.

Further, the analyzing circuit 202 includes a clock correction/countercircuit 902 and a code extraction/recognition determining circuit 903.The clock correction/counter circuit 902 generates a control signal forcontrolling another circuit from the received signal. The codeextraction/recognition determining circuit 903 analyzes informationoutputted from the demodulation circuit 210 by using the control signalin accordance with a predetermined rule. In this manner, the analyzingcircuit 202 analyzes and outputs information.

The memory 203 includes a memory controller 904 and a mask ROM 905. Thememory controller 904 generates a signal for operating the mask ROM byusing the data outputted from the analyzing circuit 202. In this manner,the memory controller 904 controls an information output from the maskROM 905 while the memory 203 outputs information.

In the semiconductor device 101 shown in FIG. 9, capacitors are used asthe band-pass filter 306 and the band-pass filter 200 as an example. Oneof a pair of electrodes of the capacitor as the band-pass filter 306 isconnected to one of a pair of terminals of the antenna 304 while theother electrode of the capacitor as the band-pass filter 306 isconnected to an input of the power source circuit 307. One of a pair ofelectrodes of the capacitor as the band-pass filter 200 is connected toone of the pair of terminals of the antenna 304 while the otherelectrode of the capacitor as the band-pass filter 200 is connected toan input of the demodulation circuit 201. It is to be noted that thecapacitor as the band-pass filter 200 and the capacitor as the band-passfilter 306 may be used in common (a band-pass filter 3060 in FIG. 16).

This embodiment can be freely implemented in combination with theaforementioned embodiment modes and Embodiments 1 and 2.

Embodiment 4

In this embodiment, an example actually manufactured the semiconductordevice described with reference to FIG. 9 in Embodiment 3 is describedwith reference to FIGS. 10 and 11.

FIG. 10 is a mask layout showing a circuit 1000 besides the antenna 304in the semiconductor device 101. In FIG. 10, the same portions as thosein FIG. 9 are denoted by the same reference numerals and descriptionthereof is omitted. The resistor 100 was formed using a semiconductorlayer which is formed simultaneously with a semiconductor layer having afunction as an active layer of a thin film transistor which formsanother circuit.

FIG. 11 is a mask layout of the semiconductor device 101 including theantenna 304. In FIG. 11, the same portions as those in FIG. 9 aredenoted by the same reference numerals and description thereof isomitted.

This embodiment can be freely implemented in combination with theaforementioned embodiment modes and Embodiments 1 to 3.

Embodiment 5

FIGS. 12A and 12B show measurement results of the characteristics of thesemiconductor device 101 of the invention. The measurement was performedby changing the electric resistance of the resistor 100 in the range of500 kΩ to 2 MΩ. For comparison, a sample without the resistor 100 wasmanufactured and measured. As measurement results, waveforms of signalsapplied to an antenna connected to a reader/writer (expressed as an RWoutput in the drawings) and waveforms of a power source voltage of asemiconductor device which performs transmission and reception of datawith the reader/writer (expressed as a power source voltage in thedrawings) are shown. The frequency of a carrier wave was set at 13.56MHz. The potential of the first terminal 310 is set at a groundpotential (expressed as GND in the drawings). The holding capacitor 309was set to have a capacitance of 500 pF. In FIGS. 12A and 12B, the sameportions as those in FIGS. 4A and 4B are denoted by the same referencenumerals. The waveforms of the modulated carrier waves shown in FIGS. 4Aand 4B correspond to the RW outputs in FIGS. 12A and 12B.

FIG. 12A shows a measurement result of the characteristics of thesemiconductor device 101 using the resistor 100 having an electricresistance of 500 kΩ. FIG. 12B shows a measurement result of thecharacteristics of a semiconductor device (a conventional semiconductordevice) without the resistor 100.

As shown in FIG. 12A, in the semiconductor device 101, the power sourcevoltage is zero or the potential of the second terminal 311 is close tothe potential of the first terminal 310 in a period in which there is noRW output (period 2). Moreover, when a first signal 401 is outputted tothe semiconductor device 101, a second signal 402 is outputted from thesemiconductor device 101 in response to the first signal 401, which isseen in the RW output. Meanwhile, in a conventional semiconductor deviceof which measurement result is shown in FIG. 12B, the power sourcevoltage is not zero or the potential of the second terminal 311 is notclose to the potential of the first terminal 310 in the period in whichthere is no RW output (period 2). Moreover, even when the first signal401 is outputted to the semiconductor device in RW output, a signal inresponse to the first signal 401 is not outputted from the semiconductordevice 101 (see the waveforms 444 in FIG. 12B).

By using the resistor 100 having an electric resistance of 500 kΩ to 2MΩ in this manner, the semiconductor device 101 can be initialized andoperate normally.

It is to be noted in FIGS. 12A and 12B that the power source voltagechanges when the first signal 401 is outputted from the reader/writer(expressed by 401′ in FIGS. 12A and 12B). Moreover, the power sourcevoltage changes when the semiconductor device 101 responses, that iswhen the second signal 402 is outputted (expressed by 402′ in FIG. 12A).These changes in the power source voltage do not spoil the effect of theinvention.

This embodiment can be freely implemented in combination with theaforementioned embodiment modes and Embodiments 1 to 4.

Embodiment 6

In this embodiment, applications of the semiconductor device 101 of theinvention are described with reference to FIGS. 13A to 14E. Thesemiconductor device 101 can be applied to paper money, coins,securities, unregistered bonds, documents (a driver's license or aresident's card; see FIG. 14A), packaging containers (wrapping paper ora bottle; see FIG. 14B), recording media (see FIG. 14C) such as DVDsoftware, a compact disc, and a video tape. In addition, thesemiconductor device 101 can be applied to means of transportation suchas cars and motor bicycles (see FIG. 14D), personal belongings such asbags and glasses (see FIG. 14E), groceries, clothes, daily commodities,and electronic devices. The electronic devices include liquid crystaldisplay devices, EL display devices, television devices (also simplycalled televisions or television receivers), portable phones, and thelike.

The semiconductor device 101 can be attached to a surface of an objector embedded in an object to be fixed. For example, the semiconductordevice 101 is preferably embedded in paper of a book or in an organicresin of a package formed of an organic resin. By providing thesemiconductor device 101 in paper money, coins, securities, unregisteredbonds, documents, and the like, forgery thereof can be prevented.Moreover, by providing the semiconductor device 101 in packagingcontainers, recording media, personal belongings, groceries, clothes,daily commodities, electronic devices, and the like, efficiency of theinspection system and the system of a rental shop can be facilitated.Moreover, by providing the semiconductor device 101 in means oftransportation, forgery and theft thereof can be prevented. Byimplanting the semiconductor device 101 in living things such asanimals, each living thing can be easily identified. For example, byimplanting a wireless tag in living things such as domestic animals, itsyear of birth, sex, breed, and the like can be easily recognized.

As described above, the semiconductor device 101 of the invention can beapplied to any object (including living things).

The semiconductor device 101 has various advantages in that it cantransmit and receive data through wireless communication, it can beprocessed into various shapes, it has a wide directivity and recognitionarea depending on the selected frequency, and the like.

Next, one mode of a system utilizing the semiconductor device 101 isdescribed with reference to FIGS. 13A and 13B. A reader/writer 1302 isprovided on a side surface of a portable terminal including a displayportion 1301. The semiconductor device 101 is provided on a side surfaceof an object 1303 (see FIG. 13A). When the reader/writer 1302 is heldnear the semiconductor device 101 attached to the object 1303, thedisplay portion 1301 displays information about the object such as a rawmaterial, a place of origin, a test result of every process, a record ofcirculation, and description of the object. As another system, in thecase of carrying an object 1305 by a conveyer belt, the object 1305 canbe inspected by using the reader/writer 1304 and the semiconductordevice 101 (see FIG. 13B). In this manner, by applying the semiconductordevice 101 of the invention to a system, information can be obtainedeasily and a system with high function and high added value can beprovided.

This embodiment can be freely implemented in combination with theaforementioned embodiment modes and Embodiments 1 to 5.

This application is based on Japanese Patent Application serial no.2005-147059 filed in Japan Patent Office on 19, May, 2005, the entirecontents of which are hereby incorporated by reference.

EXPLANATION OF REFERENCE

100: resistor, 101: semiconductor device, 200: band-pass filter, 201:demodulation circuit, 202: analyzing circuit, 203: memory, 204: encodingcircuit, 205: modulation circuit, 300: reader/writer, 301: antenna, 302:control terminal, 303: wireless tag, 304: antenna, 305: signalprocessing circuit, 306: band-pass filter, 307: power source circuit,308: rectifying circuit, 309: holding capacitor, 310: first terminal,311: second terminal, 330: modulated carrier wave, 331: potential ofsecond terminal 311, 332: potential of first terminal 310, 340:thickness, 341: carrier movement direction, 351: perpendiculardirection, 352: contact hole, 361: wire, 362: wire, 363: wire, 401:first signal, 402: second signal, 444: waveform, 500: reader/writer,501: oscillation circuit, 502: encoding circuit, 503: modulationcircuit, 504: amplifier circuit, 505: antenna, 506: band-pass filter,507: amplifier circuit, 508: demodulation circuit, 509: analyzingcircuit, 510: control terminal, 600: substrate, 601: element group, 602:terminal portion, 603: conductive particle, 604: resin, 610: substrate,660: semiconductor layer, 661: base film, 662: semiconductor layer, 662a: channel forming region, 662 b: impurity region, 662 c: lowconcentration impurity region, 663: first insulating film, 664: gateelectrode, 665: third insulating film, 666: wire, 667: second insulatingfilm, 668: fourth insulating film, 701: flexible substrate, 720:wireless tag, 801: protective layer, 802: antenna, 803: protectivelayer, 804: element group, 805: one of source and drain, 806: the otherof source and drain, 807: gate electrode, 880: substrate, 881:transistor, 901: resonant capacitor, 902: clock correction/countercircuit, 903: code extraction/recognition determining circuit, 904:memory controller, 905: mask ROM, 1000: circuit, 1301: display portion,1302: reader/writer, 1303: object, 1304: reader/writer, 1305: object,1501 a: corner, 1501 b: corner, 1501 c: corner, 1502 a: corner, 1502 b:corner, 1502 c: corner

1. A semiconductor device comprising: an antenna for transmitting andreceiving a modulated carrier wave; a power source circuit including afirst terminal and a second terminal and generating a DC voltage betweenthe first terminal and the second terminal by the modulated carrierwave; a circuit using the DC voltage as a power source voltage; and aresistor connected to the first terminal and the second terminal.
 2. Asemiconductor device comprising: an antenna for transmitting andreceiving a modulated carrier wave; a power source circuit including afirst terminal and a second terminal and generating a DC voltage betweenthe first terminal and the second terminal by the modulated carrierwave; a circuit using the DC voltage as a power source voltage; and aresistor connected the first terminal and the second terminal, whereinthe power source circuit comprises a rectifying circuit which rectifiesthe modulated carrier wave and converts the modulated carrier wave to aDC signal and a holding capacitor which smoothes the DC signal outputtedfrom the rectifying circuit, and wherein the power source circuitoutputs the signal smoothed by the holding capacitor as the DC voltage.3. A semiconductor device comprising: an antenna including a pair ofterminals and transmitting and receiving a modulated carrier wave; aband-pass filter connected to one of the pair of terminals of theantenna; a power source circuit including a first terminal and a secondterminal and generating a DC voltage between the first terminal and thesecond terminal by the modulated carrier wave inputted through theband-pass filter; a circuit using the DC voltage as a power sourcevoltage; and a resistor connected to the first terminal and the secondterminal.
 4. A semiconductor device comprising: an antenna including apair of terminals and transmitting and receiving a modulated carrierwave; a band-pass filter connected to one of the pair of terminals ofthe antenna; a power source circuit including a first terminal and asecond terminal and generating a DC voltage between the first terminaland the second terminal by the modulated carrier wave inputted throughthe band-pass filter; a circuit using the DC voltage as a power sourcevoltage; and a resistor connected to the first terminal and the secondterminal, wherein the power source circuit comprises a rectifyingcircuit which rectifies the inputted modulated carrier wave through theband-pass filter the and converts the inputted modulated carrier wave toa DC signal and a holding capacitor which smoothes the DC signaloutputted from the rectifying circuit, and wherein the power sourcecircuit outputs the signal smoothed by the holding capacitor as the DCvoltage.
 5. The semiconductor device according to claim 3, wherein thesame potential is applied to the other of the pair of terminals of theantenna and the first terminal.
 6. The semiconductor device according toclaim 4, wherein the same potential is applied to the other of the pairof terminals of the antenna and the first terminal.
 7. The semiconductordevice according to claim 3, wherein the other of the pair of terminalsof the antenna and the first terminal are grounded.
 8. The semiconductordevice according to claim 4, wherein the other of the pair of terminalsof the antenna and the first terminal are grounded.
 9. The semiconductordevice according to claim 1, wherein the circuit using the DC voltage asthe power source voltage comprises a demodulation circuit whichdemodulates the modulated carrier wave, an analyzing circuit whichanalyzes data demodulated by the demodulation circuit, and a memorywhich operates based on the data analyzed by the analyzing circuit. 10.The semiconductor device according to claim 2, wherein the circuit usingthe DC voltage as the power source voltage comprises a demodulationcircuit which demodulates the modulated carrier wave, an analyzingcircuit which analyzes data demodulated by the demodulation circuit, anda memory which operates based on the data analyzed by the analyzingcircuit.
 11. The semiconductor device according to claim 3, wherein thecircuit using the DC voltage as the power source voltage comprises ademodulation circuit which demodulates the modulated carrier wave, ananalyzing circuit which analyzes data demodulated by the demodulationcircuit, and a memory which operates based on the data analyzed by theanalyzing circuit.
 12. The semiconductor device according to claim 4,wherein the circuit using the DC voltage as the power source voltagecomprises a demodulation circuit which demodulates the modulated carrierwave, an analyzing circuit which analyzes data demodulated by thedemodulation circuit, and a memory which operates based on the dataanalyzed by the analyzing circuit.
 13. The semiconductor deviceaccording to claim 9, wherein the circuit using the DC voltage as thepower source voltage further comprises an encoding circuit which encodesthe data read from the memory, and a modulation circuit which modulatesa carrier wave in accordance with the data encoded by the encodingcircuit.
 14. The semiconductor device according to claim 10, wherein thecircuit using the DC voltage as the power source voltage furthercomprises an encoding circuit which encodes the data read from thememory, and a modulation circuit which modulates a carrier wave inaccordance with the data encoded by the encoding circuit.
 15. Thesemiconductor device according to claim 11, wherein the circuit usingthe DC voltage as the power source voltage further comprises an encodingcircuit which encodes the data read from the memory, and a modulationcircuit which modulates a carrier wave in accordance with the dataencoded by the encoding circuit.
 16. The semiconductor device accordingto claim 12, wherein the circuit using the DC voltage as the powersource voltage further comprises an encoding circuit which encodes thedata read from the memory, and a modulation circuit which modulates acarrier wave in accordance with the data encoded by the encodingcircuit.
 17. The semiconductor device according to claim 9, wherein thememory is any one of a DRAM, an SRAM, a FeRAM, a mask ROM, an EPROM, anEEPROM, and a flash memory.
 18. The semiconductor device according toclaim 10, wherein the memory is any one of a DRAM, an SRAM, a FeRAM, amask ROM, an EPROM, an EEPROM, and a flash memory.
 19. The semiconductordevice according to claim 11, wherein the memory is any one of a DRAM,an SRAM, a FeRAM, a mask ROM, an EPROM, an EEPROM, and a flash memory.20. The semiconductor device according to claim 12, wherein the memoryis any one of a DRAM, an SRAM, a FeRAM, a mask ROM, an EPROM, an EEPROM,and a flash memory.
 21. The semiconductor device according to claim 1,wherein the resistor has electric resistance of 500 kΩ to 2 MΩ.
 22. Thesemiconductor device according to claim 2, wherein the resistor haselectric resistance of 500 kΩ to 2 MΩ.
 23. The semiconductor deviceaccording to claim 3, wherein the resistor has electric resistance of500 kΩ to 2 MΩ.
 24. The semiconductor device according to claim 4,wherein the resistor has electric resistance of 500 kΩ to 2 MΩ.
 25. Thesemiconductor device according to claim 1, wherein the resistor isformed by a semiconductor layer.
 26. The semiconductor device accordingto claim 2, wherein the resistor is formed by a semiconductor layer. 27.The semiconductor device according to claim 3, wherein the resistor isformed by a semiconductor layer.
 28. The semiconductor device accordingto claim 4, wherein the resistor is formed by a semiconductor layer. 29.The semiconductor device according to claim 1, wherein the circuit usingthe DC voltage as the power source voltage comprises a thin filmtransistor, and wherein the resistor is formed by a semiconductor layerformed simultaneously with a semiconductor layer which functions as anactive layer of the thin film transistor.
 30. The semiconductor deviceaccording to claim 2, wherein the circuit using the DC voltage as thepower source voltage comprises a thin film transistor, and wherein theresistor is formed by a semiconductor layer formed simultaneously with asemiconductor layer which functions as an active layer of the thin filmtransistor.
 31. The semiconductor device according to claim 3, whereinthe circuit using the DC voltage as the power source voltage comprises athin film transistor, and wherein the resistor is formed by asemiconductor layer formed simultaneously with a semiconductor layerwhich functions as an active layer of the thin film transistor.
 32. Thesemiconductor device according to claim 4, wherein the circuit using theDC voltage as the power source voltage comprises a thin film transistor,and wherein the resistor is formed by a semiconductor layer formedsimultaneously with a semiconductor layer which functions as an activelayer of the thin film transistor.
 33. The semiconductor deviceaccording to claim 29, wherein an impurity element which impartsconductivity is added to the semiconductor layer of the resistor. 34.The semiconductor device according to claim 30, wherein an impurityelement which imparts conductivity is added to the semiconductor layerof the resistor.
 35. The semiconductor device according to claim 31,wherein an impurity element which imparts conductivity is added to thesemiconductor layer of the resistor.
 36. The semiconductor deviceaccording to claim 32, wherein an impurity element which impartsconductivity is added to the semiconductor layer of the resistor. 37.The semiconductor device according to claim 29, wherein an impurityelement which imparts conductivity is added to the semiconductor layerof the resistor at an approximately the same concentration as a channelforming region of the thin film transistor.
 38. The semiconductor deviceaccording to claim 30, wherein an impurity element which impartsconductivity is added to the semiconductor layer of the resistor at anapproximately the same concentration as a channel forming region of thethin film transistor.
 39. The semiconductor device according to claim31, wherein an impurity element which imparts conductivity is added tothe semiconductor layer of the resistor at an approximately the sameconcentration as a channel forming region of the thin film transistor.40. The semiconductor device according to claim 32, wherein an impurityelement which imparts conductivity is added to the semiconductor layerof the resistor at an approximately the same concentration as a channelforming region of the thin film transistor.
 41. The semiconductor deviceaccording to claim 1, wherein the antenna is any one of a dipoleantenna, a patch antenna, a loop antenna, and a Yagi antenna.
 42. Thesemiconductor device according to claim 2, wherein the antenna is anyone of a dipole antenna, a patch antenna, a loop antenna, and a Yagiantenna.
 43. The semiconductor device according to claim 3, wherein theantenna is any one of a dipole antenna, a patch antenna, a loop antenna,and a Yagi antenna.
 44. The semiconductor device according to claim 4,wherein the antenna is any one of a dipole antenna, a patch antenna, aloop antenna, and a Yagi antenna.
 45. The semiconductor device accordingto claim 1, wherein the modulated carrier wave is formed by modulating acarrier wave in an analog modulation method or a digital modulationmethod.
 46. The semiconductor device according to claim 2, wherein themodulated carrier wave is formed by modulating a carrier wave in ananalog modulation method or a digital modulation method.
 47. Thesemiconductor device according to claim 3, wherein the modulated carrierwave is formed by modulating a carrier wave in an analog modulationmethod or a digital modulation method.
 48. The semiconductor deviceaccording to claim 4, wherein the modulated carrier wave is formed bymodulating a carrier wave in an analog modulation method or a digitalmodulation method.
 49. The semiconductor device according to claim 1,wherein the antenna transmits and receives the modulated carrier wave byany one of an electromagnetic coupling method, an electromagneticinduction method, and a radio wave method.
 50. The semiconductor deviceaccording to claim 2, wherein the antenna transmits and receives themodulated carrier wave by any one of an electromagnetic coupling method,an electromagnetic induction method, and a radio wave method.
 51. Thesemiconductor device according to claim 3, wherein the antenna transmitsand receives the modulated carrier wave by any one of an electromagneticcoupling method, an electromagnetic induction method, and a radio wavemethod.
 52. The semiconductor device according to claim 4, wherein theantenna transmits and receives the modulated carrier wave by any one ofan electromagnetic coupling method, an electromagnetic induction method,and a radio wave method.